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From: James Meyer
Newsgroups: sci.electronics.design
Subject: Re: Thermal effects of potting compound?
Message-ID:
References:
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Date: Wed, 16 Oct 2002 22:53:56 GMT
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On Wed, 16 Oct 2002 14:16:35 +0100, "Tom Faloon"
wroth:
>
>If you don't have forced air cooling, then turning the board upside down
>will probably degrade the cooling performance considerably, because you will
>discourage convection. Some heat will be lost by convection off the upper
>side of the board, but the heat will have to pass through the PCB material,
>which is not a very good conductor. Cooling will be very inefficient
>compared with having the board 'right way up'.
That may be true, but only if the surface mount parts are tall enough to
stick up above the stagnant layer of air that surrounds the board. Most parts
won't be that tall.
Jim